Like bacteria, viruses are organisms that spread airborne diseases as mild as the common cold and as serious as severe acute respiratory syndrome (SARS) through coughs, sneezes and improperly maintained ventilation systems.

Tobacco Smoke

Tobacco Smoke: 0.01 – 1 micron

Sidestream smoke has higher concentrations of cancer-causing agents (carcinogens) than mainstream smoke. And, it has smaller particles than mainstream smoke, which make their way into the lungs and the body's cells more easily.

Soot

Soot: 0.01 – 0.3 microns

Long-term exposure to urban air pollution containing soot increases the risk of coronary heart disease, according to a major study published in New England Journal of Medicine in 2007.

0.01

0.1

Ultrafine Particles

Approx.9% of all airborne particles

0.3

Pet Dander

Pet Dander: 0.1 – 25 microns

Pet dander is the old skin and fur that pets shed. Animal dander is very small and can become attached to your clothingeven if you do not own a pet. Dander can be found everywhere: floors, carpets, walls, furniture, bedding, even the ceilings. Pet dander is a known asthma and allergy trigger.

Dust Mites Allergens

Dust Mites Allergens: 0.2 – 25 microns

House dust mites are considered to be the most common cause of asthma and allergic symptoms worldwide. Dust mites themselves do not cause an allergic reaction, however, their dung-pellets are an irritant to sensitive people and can cause breathing difficulties. They thrive in warm, humid, dark conditions such as mattresses, carpets, sheets, pillows, and upholstery.

Bacteria

Bacteria: 0.5 – 10 microns

People spread bacteria through the air when they cough and sneeze, transmitting respiratory diseases and triggering symptoms in asthma sufferers. Bacteria can also grow inside poorly maintained ventilation systems, which spread it into the circulating air.

1

Household Dust

Household Dust: 1 – 100 micron

Dust may worsen hay fever. Circulating outdoor air through a house by keeping doors and windows open, or at least slightly ajar, may reduce the risk of hay fever-causing dust. In colder climates, occupants seal even the smallest air gaps, and eliminate outside fresh air circulating inside the house. So it is essential to manage dust and airflow.

2.5

Fine Particles

Less than1% of all airborne particles

10

Mold Spores

Mold Spores: 8 – 80 microns

Mold and fungus are commonly found in most homes and may be found in the air ducts of your heating/cooling system. They tend to float throughout the house, and form new colonies where they land. Fungus spores have been known to increase the chances of developing asthma.

Pollen

Pollen: 10 – 100 microns

One of the most common allergens is pollen. It affects the nose, eyes, and mouth making it difficult to breathe. Most pollen that produces allergic reactions is from trees, grasses, and weeds.

100

Coarse Particles

Affected Organs »

Brain

Lungs

Throat

Eyes

Nose

Heart

Kidneys

Liver

Select one of the particlesabove to see how it affects your body

Ultrafine particles are airborne particles less than 0.1 microns in diameter. In sheer number, they represent more than 90% of all airborne pollutants. Ultrafine particles are inhaled and deposited directly into the lungs, where they penetrate tissue and can be absorbed directly into the bloodstream. Through the bloodstream, they can reach any organ or area of the human body.

FINE PARTICLES (PM2.5) | Greater than 9% of all airborne particles

Fine particles (also known as PM2.5) are particulate matter that is less than or equal to 2.5 microns in diameter. Fine particles penetrate deeply into the lungs, into areas known as small airways and into the primary air exchange areas of the lungs. Fine particles come from vehicle exhaust, gas and chemical reactions, tobacco smoke, burning candles and other indoor and outdoor sources.

COARSE PARTICLES (PM10) | Less than 1% of all airborne particles

Coarse particles (also known as PM10) are those with a diameter between 2.5 and 10 microns in diameter. Coarse particles are deposited almost exclusively in the nose and throat. They are not generally inhalable directly into the lungs. Examples of PM10 include coal dust, fly ash, some components of wood smoke, asbestos fibers, and roadside particles from tires and brakes. This category also includes dust, some pollen and mold spores.

Left Column

AirVisual data: Hazardous Delhi pollution is the longest on record

In 2019, Delhi air quality was in the hazardous range for nine consecutive days, the longest spell of hazardous air quality since public records began.

Delhi residents entered a 10-day streak of hazardous air pollution in November 2019.

India’s capital city passed the unhealthy milestone a day after authorities introduced a temporary rule to reduce cars on the roads to try to lower pollution levels.

Overall, daily Delhi air quality was hazardous from Sunday, October 27 to Tuesday, November 5.

During that time, the air was coated with a thick brownish haze. City schools have closed. Flights have been canceled or diverted because of poor visibility. Authorities have enacted a measure to take 4 million cars off the roads by only allowing cars with odd or even license plates on alternate days.

On the worst day – Sunday, Nov. 3 – the average concentration of PM2.5 (fine particulate matter) across the whole city was 509.2 micrograms per cubic meter (µg/m3), a 568 on the U.S. Air Quality Index and more than 50 times the World Health Organization’s recommended annual guideline.

Delhi hazardous air pollution

Delhi residents breathe through at least nine days of consecutive hazardous air pollution, as shown on the AirVisual air quality app

Delhi’s air quality was consistently unhealthy since Diwali in late October when a ban on conventional firecrackers failed to stop pollution levels soaring during India’s biggest annual festival.

Why is Delhi's air quality so bad?

The sources of Delhi’s pollution generally include vehicle emissions, industry, construction, power plants, and waste-burning.

Current smog levels have been made worse by weather conditions and the actions of farmers in the neighboring states of Punjab and Haryana, who burn fields to clear the land after crops have been harvested – known as stubble burning – producing smoke that travels across large distances. There is rarely an immediate let-up in this smoke, as the harvest season lasts until mid-November. Major fires can be seen on the AirVisual air quality and fires map.

Meanwhile, falling temperatures and a lack of rain and winds in Delhi have meant pollutants have stayed around for longer.

Delhi’s previous record was eight consecutive days of hazardous air quality between Nov. 7-14, 2017. The publishing of real-time air quality data in Delhi started in January 2016.

The city average is worked out using the median of all stations reporting timely PM2.5 data across Delhi. During Delhi’s bout of hazardous air pollution, areas of the city experienced pollution levels more than 150 times the WHO guideline – for example, in Vivek Vihar the U.S. Air Quality Index reached 1604– with a PM2.5 concentration of 1542 µg/m3 – on Sunday, Nov. 3.

ABOUT IQAIR

IQAir is a Swiss-based air quality technology company that since 1963 empowers individuals, organizations and communities to breathe cleaner air through information, collaboration and technology solutions.

ABOUT IQAIRIQAir is a Swiss-based air quality technology company that since 1963 empowers individuals, organizations and communities to breathe cleaner air through information, collaboration and technology solutions.